Lovesick is a collaboration between the 3x Grammy-nominated singer Raheem DeVaughn and the legendary hip-hop producer, Apollo Brown, best known for making hip-hop so grimy that it permanently lodges in your lungs and underneath your fingernails. It is a work of startling beauty, a blend of modern R&B, classic soul, and guttural funk that recalls Smokey Robinson, Al Green, and Marvin Gaye. Yet it doesn’t sound out of step alongside DeVaughn’s peers The-Dream, Anderson .Paak, and Miguel.